Stiffener tab for a spindle motor base plate

ABSTRACT

An apparatus and method are provided for stiffening a base plate of a spindle motor to improve shock resistance and vibration response, and thereby increase reliability and performance of a disc drive memory system. A stiffener tab for stiffening a base plate is connected to the base plate, extends from the base plate, and is dimensioned to fit adjacent to a stator tooth. Stiffening of a base plate is especially useful in the case of stamped base plate designs that typically have uniform thickness, whereas cast base plate designs are formed with thicker sections. In an aspect, the present invention stiffens a motor cup portion of the base plate, and replaces stiffness lost by removal of material from the base plate to form holes for recessing a stator into the base plate. Axial and angular displacement of a spindle motor during shock events and vibration are decreased.

BACKGROUND

Disc drive memory systems store digital information that is recorded onconcentric tracks on a magnetic disc medium. At least one disc isrotatably mounted on a spindle, and the information, which can be storedin the form of magnetic transitions within the discs, is accessed usingread/write heads or transducers. A drive controller is typically usedfor controlling the disc drive system based on commands received from ahost system. The drive controller controls the disc drive to store andretrieve information from the magnetic discs. The read/write heads arelocated on a pivoting arm that moves radially over the surface of thedisc. The discs are rotated at high speeds during operation using anelectric motor located inside a hub or below the discs. Magnets on thehub interact with a stator to cause rotation of the hub relative to thestator. One type of motor has a spindle mounted by means of a bearingsystem to a motor shaft disposed in the center of the hub. The bearingspermit rotational movement between the shaft and the sleeve, whilemaintaining alignment of the spindle to the shaft.

Disc drive memory systems are being utilized in progressively moreenvironments besides traditional stationary computing environments.Recently, these memory systems are incorporated into devices that areoperated in mobile environments including digital cameras, digital videocameras, video game consoles and personal music players, in addition toportable computers. These mobile devices are frequently subjected tovarious magnitudes of mechanical shock as a result of handling. As such,performance and design needs have intensified including improvedresistance to shock events including axial and angular shock resistance,vibration response, and improved robustness.

The read/write heads must be accurately aligned with the storage trackson the disc to ensure the proper reading and writing of information.Moreover, a demand exists for increased storage capacity and smallerdisc drives, which has led to the design of higher recording arealdensity such that the read/write heads are placed increasingly closer tothe disc surface. Precise alignment of the heads with the storage tracksis needed to allow discs to be designed with greater track densities,thereby allowing smaller discs and/or increasing the storage capacity ofthe discs. Because rotational accuracy is critical, many disc drivespresently utilize a spindle motor having a fluid dynamic bearing (FDB)situated between a shaft and sleeve to support a hub and the disc forrotation. In a hydrodynamic bearing, a lubricating fluid is providedbetween a fixed member bearing surface and a rotating member bearingsurface of the disc drive. Hydrodynamic bearings, however, suffer fromsensitivity to external loads or mechanical shock. In particular, thestiffness of the fluid dynamic bearing is critical so that the rotatingload is accurately and stably supported on the spindle without wobble ortilt.

Traditional base plate designs in larger disc drives are typically castfrom aluminum. However, in the field of spindle motors for small formfactor hard disc drives, thin stamped base plates are often employed forcost and manufacturing advantages. These stamped base plates aretypically a steel material of generally uniform thickness, and thereforedo not allow for localized thicker sections to optimize the tradeoff ofstiffness versus space savings. Also, small form factor disc drives aretypically so impacted for space due to slimness requirements that holesare now commonly punched out of the base plate into which stator windingcoils are recessed to lower the stator height and allow more spaceinside the disc drive without increasing the size of the disc drive.However, forming a hole in a base plate and removing material from thebase plate further lessens vibration resistance of an already thin baseplate and thereby increases susceptibility to read-write errors of thedisc caused by any vibration. Also, by removing material from the baseplate, the base plate may become more susceptible to permanentdeformation in the case of a shock event, in which, for example, themotor is jarred or dropped.

SUMMARY

An apparatus and method are described herein for stiffening a base plateof a spindle motor. A bearing is defined between a stationary componentand a rotatable component, wherein the stationary component and therotatable component are positioned for relative rotation. The stationarycomponents include a base plate and a stator. The stator comprises atleast one stator tooth. A stiffener tab, connected to, or integral with,the base plate, extends from the base plate, and is dimensioned to fitadjacent to at least one stator tooth, for stiffening the base plate.These and various other features and advantages will be apparent from areading of the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and many of the attendant advantages of thisinvention will become more readily appreciated by reference to thefollowing detailed description, when taken in conjunction with theaccompanying drawings, wherein:

FIG. 1 is a top plan view of a disc drive data storage system in whichthe present invention is useful, in accordance with an embodiment of thepresent invention;

FIG. 2 is a sectional side view of a contemporary spindle motor used ina disc drive data storage system incorporating a contemporary base platewith holes into which stator teeth are recessed for space savings;

FIG. 3 is a perspective view of a portion of a base plate for a spindlemotor as in FIG. 2, the base plate having holes for receiving a recessedstator;

FIG. 4 is a plan view of a portion of a base plate wherein a hole isbeing formed for receiving a recessed stator for a spindle motor,wherein a stiffener tab is being formed from a portion of the base platethat is ultimately displaced to form the hole, in accordance with anembodiment of the present invention;

FIG. 5 is a plan view of a portion of a base plate wherein a hole isbeing formed for receiving a recessed stator for a spindle motor,wherein two stiffener tabs are being formed from a portion of the baseplate that is ultimately displaced to form the hole, in accordance withanother embodiment of the present invention;

FIG. 6 is a perspective view of a portion of a base plate as in FIG. 4,wherein the stiffener tabs extend at a 90 degree angle with respect to aradially extending span of the base plate, in accordance with anembodiment of the present invention;

FIG. 7 is a perspective view of a plurality of stator teeth forattaching to a stationary component of a spindle motor, whereinstiffener tabs extend from a base plate and adjacent to the statorteeth, in accordance with an embodiment of the present invention;

FIG. 8 is a plan view of a plurality of stator teeth for attaching to astationary component of a spindle motor, wherein stiffener tabs extendfrom a base plate between the stator teeth within an unoccupied area, inaccordance with another embodiment of the present invention;

FIG. 9A is a sectional side view of a stator tooth partially recessedinto a hole in a base plate for a spindle motor, wherein a stiffener tabextends from the base plate and attaches to the stator tooth, inaccordance with an embodiment of the present invention;

FIG. 9B is a sectional side view of stator windings partially recessedinto a hole in a base plate for a spindle motor, in an exampleembodiment of FIG. 9A, wherein a stiffener tab extends from the baseplate and attaches to the stator tooth, in accordance with an embodimentof the present invention;

FIG. 10 is a sectional side view of a stator tooth partially recessedinto a hole in a base plate for a spindle motor, wherein a stiffener tabextends from the base plate, in accordance with an embodiment of thepresent invention;

FIG. 11 is a sectional side view of a stator tooth partially recessedinto a hole in a base plate for a spindle motor, wherein two stiffenertabs extend from the base plate and attach to the stator tooth, inaccordance with an embodiment of the present invention;

FIG. 12 is a sectional side view of a stator tooth partially recessedinto a hole in a base plate for a spindle motor, wherein two stiffenertabs extend from the base plate, in accordance with an embodiment of thepresent invention; and

FIG. 13 is a sectional side view of a stator tooth, a base plate andstiffener tabs, for a spindle motor, wherein the stiffener tabs extendfrom the base plate and are positioned axially below the stator toothwhile being circumferentially adjacent to the stator tooth, inaccordance with an embodiment of the present invention.

DETAILED DESCRIPTION

Exemplary embodiments are described with reference to specificconfigurations. Those of ordinary skill in the art will appreciate thatvarious changes and modifications can be made while remaining within thescope of the appended claims. Additionally, well-known elements,devices, components, methods, process steps and the like may not be setforth in detail in order to avoid obscuring the invention.

An apparatus and method are described herein for stiffening a base plateof a spindle motor to improve shock resistance and vibration response,and thereby increase reliability and performance of a disc drive memorysystem. Stiffening of a base plate is especially useful in the case ofstamped base plate designs that typically have uniform thickness,whereas cast base plate designs are formed with thicker sections. When abase plate is cast, the present invention provides, in an embodiment, astiffener tab formed along with the casting. In an embodiment, thepresent invention stiffens a motor cup portion of the base plate,thereby replacing stiffness lost by removal of material from the baseplate used to form holes for recessing a stator.

Axial and angular displacement of a spindle motor during shock eventsand vibration are decreased. The improved axial and angular stiffnessresults in the read/write heads of a storage device being accuratelyaligned with storage tracks on a disc, when the device is subjected tovibration. This allows discs to be designed with increased trackdensities, and also allows for smaller discs and/or increased storagecapacity of discs. Also, changes can be made to the natural frequency ofthe base plate axial and bending modes of vibration, therefore thepresent invention can further provide improved acoustic performance ofthe motor-base system.

It will be apparent that features of the discussion and claims may beutilized with disc drive memory systems, low profile disc drive memorysystems, spindle motors, brushless DC motors, various fluid dynamicbearing designs including hydrodynamic and hydrostatic bearings, andother motors employing a stationary and a rotatable component, includingmotors employing conical bearings. Further, embodiments of the presentinvention may be employed with a fixed shaft or a rotating shaft. Also,as used herein, the terms “axially” or “axial direction” refers to adirection along a centerline axis length of the shaft (i.e., along axis260 of shaft 202 shown in FIG. 2), and “radially” or “radial direction”refers to a direction perpendicular to the centerline axis 260, andpassing through centerline axis 260. Also, as used herein, theexpressions indicating orientation such as “upper”, “lower”, “top”,“bottom”, “height” and the like, are applied in a sense related tonormal viewing of the figures rather than in any sense of orientationduring particular operation, etc. These orientation labels are providedsimply to facilitate and aid understanding of the figures as describedin this Description and should not be construed as limiting.

Referring to the drawings wherein identical reference numerals denotethe same elements throughout the various views, FIG. 1 illustrates a topplan view of a typical disc drive data storage system 110 in which thepresent invention is useful. Clearly, features of the discussion andclaims are not limited to this particular design, which is shown onlyfor purposes of the example. Disc drive 110 includes base plate 112 thatis combined with cover 114 forming a sealed environment to protect theinternal components from contamination by elements outside the sealedenvironment. Disc drive 110 further includes disc pack 116, which ismounted for rotation on a spindle motor (described in FIG. 2) by discclamp 118. Disc pack 116 includes a plurality of individual discs, whichare mounted for co-rotation about a central axis. Each disc surface hasan associated head 120 (read head and write head), which is mounted todisc drive 110 for communicating with the disc surface. In the exampleshown in FIG. 1, heads 120 are supported by flexures 122, which are inturn attached to head mounting arms 124 of actuator body 126. Theactuator shown in FIG. 1 is a rotary moving coil actuator and includes avoice coil motor, shown generally at 128. Voice coil motor 128 rotatesactuator body 126 with its attached heads 120 about pivot shaft 130 toposition heads 120 over a desired data track along arc path 132. Thisallows heads 120 to read and write magnetically encoded information onthe surfaces of discs 116 at selected locations.

A flex assembly provides the requisite electrical connection paths forthe actuator assembly while allowing pivotal movement of the actuatorbody 126 during operation. The flex assembly (not shown) terminates at aflex bracket for communication to a printed circuit board mounted to thebottom side of disc drive 110 to which head wires are connected; thehead wires being routed along the actuator arms 124 and the flexures 122to the heads 120. The printed circuit board typically includes circuitryfor controlling the write currents applied to the heads 120 during awrite operation and a preamplifier for amplifying read signals generatedby the heads 120 during a read operation.

Referring to FIG. 2, a sectional side view is illustrated of acontemporary spindle motor as used in a disc drive data storage system110, incorporating a base plate 220 with holes 221 into which statorwindings 217 are recessed for space savings. This fluid dynamic bearingmotor includes a rotatable component that is relatively rotatable abouta stationary component, defining a journal bearing 206 therebetween. Inthis example, the rotatable components include shaft 202 and hub 210.Hub 210 includes a disc flange, which supports disc pack 116 (shown inFIG. 1) for rotation about axis 260 of shaft 202. Shaft 202 and hub 210are integral with backiron 215. One or more magnets 216 are attached toa periphery of backiron 215. The magnets 216 interact with a laminationstack 214 attached to the base 220 to cause the hub 210 to rotate.Magnet 216 can be formed as a unitary, annular ring or can be formed ofa plurality of individual magnets that are spaced about the periphery ofhub 210. Magnet 216 is magnetized to form one or more magnetic poles.The stationary components include sleeve 204 and stator 211, which areaffixed to base plate 220. Bearing 206 is established between the sleeve204 and the rotating shaft 202. A thrust bearing 207 is establishedbetween hub 210 and sleeve 204. Thrust bearing 207 provides an upwardforce on hub 210 to counterbalance the downward forces including theweight of hub 210, axial forces between magnet 216 and base plate 220,and axial forces between stator lamination stack 214 and magnet 216. Inthe case of a fluid dynamic bearing spindle motor, a fluid, such aslubricating oil fills the interfacial regions between shaft 202 andsleeve 204, and between hub 210 and sleeve 204, as well as between otherstationary and rotatable components. While the present figure isdescribed herein with a lubricating fluid, those skilled in the art willappreciate that useable fluids include a liquid, a gas, or a combinationof a liquid and gas.

Since memory systems are being utilized in progressively moreenvironments, a demand exists for smaller and thinner motors, andconsequently thinner base plates. FIG. 3 is a perspective view of aportion of a base plate 300 for a spindle motor as used in FIG. 2.Current thicknesses for a stamped steel base plate in a small formfactor hard disc drive range from 0.2 to 0.8 millimeters. As shown, baseplate 300 includes holes 304 for receiving a recessed stator, forfurther reducing the axial thickness of a motor. Holes 304 formed intobase plate 300 further reduce the stiffness of an already thin baseplate 300.

FIG. 4 is a plan view of a portion of a base plate 310 in which a hole312 is being formed for receiving a recessed stator for a spindle motor.A stiffener tab 314 is formed from a portion of the base plate 310, andthe stiffener tab 314 is ultimately displaced to form the hole 312, inthe case of a stamped steel base plate, in accordance with an embodimentof the present invention. The material that forms stiffener tab 314 isthus utilized, rather than discarded as is typically carried out. A bendis eventually formed in base plate 310 at a position represented atmargin 316, extending stiffener tab 314 from base plate 310 into themotor cup space. The number and placement of stiffener tabs about a baseplate is chosen to optimize the stiffness and stability of the baseplate. In an embodiment, all stator holes form a stiffener tab, while inanother embodiment, less than all stator holes form a stiffener tab.

The portion of the base plate that is displaced and defines the hole isutilized to form one stiffener tab, two stiffener tabs, or more than twostiffener tabs. FIG. 5 illustrates two stiffener tabs 324A and 324Bbeing formed from a portion of the base plate 320 that ultimatelydisplaced to form the hole 322, in accordance with another embodiment ofthe present invention. In this embodiment, a bend is ultimately formedin base plate 320 at a position represented at margins 326A and 326B,extending stiffener tabs 324A and 324B from base plate 320 into themotor cup space. By way of these stiffener tabs, the present inventioncan serve to reduce axial and angular displacement of a spindle motorduring shock events and vibration. By improving shock resistance andvibration response, consistently accurate alignment of the read/writeheads of a storage device with storage tracks on a disc can result. Thisin turn allows discs to be designed with increased track densities, andalso allows for smaller discs and/or increased storage capacity ofdiscs.

Additionally, in an embodiment, the present invention adjusts thenatural frequency of the base plate axial and bending modes ofvibration. The natural frequency is tuned by adjusting the number ofstiffener tabs employed or by adjusting the size of the stiffener tabssuch as length and height changes. Improved acoustic performance of themotor-base system can also be provided by the present invention. Incases where a base design has a natural frequency aligned with theelectromagnetic frequencies of the motor, the natural frequencies of thebase can be shifted using the stiffener tabs to reduce the baseexcitation and resulting acoustic emissions. Thus, the present inventionis employed to adjust and benefit the system acoustic output as well.Additionally, the stiffener tabs can be used to improve effects fromoperating vibration response when the disc drive is subjected toexternal vibration from its environment. As an example, when a discdrive is vibrated at the same natural frequency as the motor basesystem, then the disc drive vibration response will considerablyincrease. In an embodiment, the present invention shifts the motor baseresonance to a frequency that is out of range of any expected operatingvibration, thus reducing the response to any operating vibration.

Referring to FIG. 6, a perspective view is illustrated of a portion of abase plate as in FIG. 4, wherein the stiffener tab 334 extends at a 90degree angle with respect to a radially extending span 332 of the baseplate 330, in accordance with an embodiment of the present invention.The radially extending span 332 is defined herein as perpendicular tothe axis 340 of a shaft (like the axis 260 of shaft 202 shown in FIG.2). The stiffener tab 334 is connected to the base plate and extendsfrom the base plate. The stiffener tab 334 is formed either from aportion of the base plate 330 that is displaced to form the hole 335, orformed from a separate material that is attached to the base plate 330using, for example, an adhesive. The base plate 330 may be created byeither a stamping process or a casting process. When the base plate 330is cast, the stiffener tab 334 can alternatively be formed along withthe casting. Holes may be defined through a cast aluminum base plate, oralternatively, depressions are formed in the base plate to minimize thebase plate thickness.

Stiffener tab 334 can be formed to extend at angles other than a 90degree angle with respect to a radially extending span 332 of the baseplate 330. The selected angle for the stiffener tab 334 can be based onthe available area for the stiffener tab 334, as well as the resultingstiffness and natural frequency of the base plate 330. The availablearea for the stiffener tab 334 is based on the clearance between thestator windings.

Turning now to FIG. 7, a perspective view is shown of a plurality ofstator teeth 420 for attaching to a stationary component of a spindlemotor. The stiffener tabs 434 extend from base plate 430 and adjacent tothe stator teeth 420, in accordance with an embodiment of the presentinvention. The stator teeth 420 include lamination stack 424 and statorwindings 422. It is to be appreciated that the present inventionstiffener tab 434 can be employed with a stator having only one statortooth, and can also be employed with a typical stator having more thanone stator tooth, such as a stator with nine stator teeth. In thisexample, stator 410 includes twelve stator teeth. The stiffener tab 434is positioned circumferentially adjacent to the first stator tooth 420Aand the second stator tooth 420B.

Stiffener tab 434 is formed from a portion of the base plate 430 that isdisplaced and defines a hole 435 within the base plate 430, and thus thestiffener tab 434 is situated adjacent to the hole 435. Here, thestiffener tabs 434 are dimensioned to fit adjacent to the stator teeth.When the stiffener tab is formed from a hole, the stiffener tab may betrimmed or otherwise shaped to fit adjacent to the stator teeth. Whenthe stiffener tab is attached to a base plate, rather than being formedfrom a portion of a base plate that is displaced and defines a holewithin the base plate, then the stiffener tab can be selectively shapedand placed.

FIG. 8 illustrates a plan view of a plurality of stator teeth 520 forattaching to a stationary component of a spindle motor. As compared withthe stator illustrated in FIG. 7, the stator illustrated in FIG. 8 isdesigned for positioning outboard of an interacting magnet. Thestiffener tabs 534 extend from a base plate 530 between the stator teethwithin an unoccupied area. In this embodiment, the stiffener tabs 534are formed with dimensions (i.e., length, width, and height) for fillingan unoccupied area defined adjacent to the stator teeth 520, such thatthe dimensions of the stiffener tabs 534 are maximized to an extentwithout interfering with any motion of the spindle bearing system. Thestiffener tabs can be shaped as desired including having a step, aslope, or maximized in size to fit adjacent to a structure. The numberof the stiffener tabs utilized is chosen depending on factors includingthe available space between stator teeth, base manufacturingconstraints, and structural resonance requirements.

As illustrated in FIG. 9A, a sectional side view is shown of a statortooth 606 partially recessed into a hole 602 in a base plate 600 for aspindle motor. The portion of the stator tooth 606 that is recessed intohole 602 is either: i) a portion of the stator windings; or ii) aportion of the stator lamination stack; or iii) a portion of the statorwindings and a portion of the stator lamination stack. A stiffener tab604 extends from the base plate 600 and attaches to at least a portionof the stator tooth 606, in accordance with an embodiment of the presentinvention. As an example, the stiffener tab 604 may be attached to thestator windings only, to the stator lamination stack only, or to boththe stator windings and stator lamination stack. Again, as describedherein “stator tooth” or “stator teeth” include both a stator laminationstack and the stator windings about the respective stator laminationstack. If the stiffener tab 604 is electrically conductive, then it maybe electrically insulated from stator tooth 606 to avoid any electricalshorting of the stator tooth 606. The stiffener tab 604 is positionedcircumferentially adjacent to the stator tooth 606, and, optionally, anadhesive 605 interlocks the stator tooth 606 and the stiffener tab 604,thereby dampening any vibration of the stator tooth 606, and addingstructural support to stiffen the base plate assembly. The adhesivedirectly connects the stiffener tab to the stator lamination stack, tothe stator windings, or to both the stator lamination stack and thestator windings. In an alternative design, the stator tooth ispositioned axially above the base plate, without being recessed into ahole, while the stiffener tab 604 is positioned circumferentiallyadjacent to the stator tooth. In a further alternative design, thestiffener tab is positioned axially below a stator tooth, wherein thestator tooth is not partially recessed into a hole in a base plate,although in this design the stiffener tab occupies axial space.

FIG. 9B illustrates an example embodiment of FIG. 9A, wherein a portionof a stator tooth that is recessed into hole 611 in the base plate 610is a portion of the stator windings 613, without the lamination stack612 similarly being recessed into the hole 611. Also, an adhesive 615 isshown bonding stiffener tab 614 to the stator winding 613. This designis useful for a stamped base plate 610.

As illustrated in FIG. 10, a sectional side view is shown of a statortooth 626 partially recessed into a hole 622 in a base plate 620 for aspindle motor. A stiffener tab 624 extends from the base plate 620, inaccordance with an embodiment of the present invention. The stiffenertab 624 is positioned circumferentially adjacent to the stator tooth626, and the stiffener tab 624 remains separated from the stator tooth626, rather than connected via an adhesive as in FIG. 9. Again, in analternative design, the stator tooth is positioned axially above thebase plate, without being recessed into a hole.

FIG. 11 is a sectional side view of a stator tooth 646 partiallyrecessed into a hole 642 in a base plate 640 for a spindle motor. Twostiffener tabs 644A and 644B extend from the base plate 640 and attachto at least a portion of the stator tooth 646. As an example, thestiffener tabs 644A and 644B may be attached to the stator windingsonly, to the stator lamination stack only, or to both the statorwindings and stator lamination stack. If the stiffener tabs 644A and644B are electrically conductive, then they may be electricallyinsulated from stator tooth 646 to avoid any electrical shorting of thestator tooth 646. The stiffener tabs 644A and 644B are positionedcircumferentially adjacent to the stator tooth 646, and, optionally, anadhesive 645 interlocks the stator tooth 646 and the stiffener tabs 644Aand 644B, thereby dampening any vibration of the stator tooth 646. Theadhesive directly connects the stiffener tabs 644A and 644B to thestator lamination stack, to the stator windings, or to both the statorlamination stack and the stator windings. The stiffener tabs 644A and644B are formed either from a portion of the base plate 640 that isdisplaced to form the hole 642 (as shown in FIG. 5), or formed from aseparate material that is attached to the base plate 640 using, forexample, an adhesive. Also, it is to be appreciated that by forming astiffener tab on each circumferential side of a stator tooth, the resultis that two stiffener tabs are formed between adjacent stator teeth.

As illustrated in FIG. 12, a sectional side view is illustrated of astator tooth 666 partially recessed into a hole 662 in a base plate 660for a spindle motor. Two stiffener tabs 664A and 664B extend from thebase plate 660. The stiffener tabs 664A and 664B are positionedcircumferentially adjacent to the stator tooth 666. The stiffener tabs664A and 664B are formed either from a portion of the base plate 660that is displaced to form the hole 662 (as shown in FIG. 5), or formedfrom a separate material that is attached to the base plate 660 using,for example, an adhesive. Again, it is to be appreciated that by forminga stiffener tab on each circumferential side of a stator tooth, theresult is that two stiffener tabs are formed between adjacent statorteeth.

As illustrated in FIG. 13, a sectional side view is shown of a statortooth 726, a base plate 720 and stiffener tabs 724A and 724B, for aspindle motor. The two stiffener tabs 724A and 724B extend from the baseplate 720 and are positioned axially below the stator tooth 726 whilebeing circumferentially adjacent to the stator tooth 726. Here,stiffener tabs 724A and 724B may be formed by a method includingattaching to base plate 720 and casting along with base plate 720, asdescribed above.

While the embodiments described illustrate a stiffener tab extendingfrom a base plate in a direction generally toward a stator, in analternative embodiment, the stiffener tab extends from a base plate witha distal end oriented in a direction 180 degrees away from the stator.

Modifications and variations may be made to the disclosed embodimentswhile remaining within the spirit and scope of the invention. Theimplementations described above and other implementations are within thescope of the following claims.

1. A spindle motor system comprising: a bearing defined between astationary component and a rotatable component, wherein the stationarycomponent and the rotatable component are positioned for relativerotation, wherein the stationary component includes a base plate and astator, and wherein the stator comprises at least one stator tooth; anda stiffener tab for stiffening the base plate, the stiffener tabextending from the base plate, and wherein: i.) at least a portion ofthe stiffener tab is dimensioned to fit and positioned circumferentiallyadjacent to the at least one stator tooth of the stator; and ii.) thestiffener tab extends along a radially extending span of the base plate.2. (canceled)
 3. The spindle motor system as in claim 1, wherein thestiffener tab is situated axially below the stator while beingcircumferentially adjacent to the stator.
 4. The spindle motor system asin claim 1, wherein the stator comprises a first stator tooth and asecond stator tooth, and wherein at least a portion of the stiffener tabis positioned circumferentially adjacent to the first stator tooth andthe second stator tooth.
 5. The spindle motor system as in claim 1,wherein the stiffener tab is formed from a portion of the base platethat is displaced and defines a hole within the base plate.
 6. Thespindle motor system as in claim 5, wherein the portion of the baseplate that is displaced and defines the hole forms either one of thestiffener tab or two of the stiffener tab.
 7. The spindle motor systemas in claim 1, wherein the stiffener tab is formed from a material thatis attached to the base plate.
 8. The spindle motor system as in claim1, wherein at least a portion of the stator is positioned within a holedefined within the base plate.
 9. The spindle motor system as in claim1, wherein the stiffener tab extends at a 90 degree angle with respectto a radially extending span of the base plate.
 10. The spindle motorsystem as in claim 1, wherein the stiffener tab is further connected toa portion of the stator for further stiffening the base plate.
 11. Thespindle motor system as in claim 1, wherein the stiffener tab is formedwith dimensions for filling an unoccupied area defined adjacent to thestator, wherein the dimensions of the stiffener tab are maximized to anextent without interfering with any motion of the spindle motor system.12. The spindle motor system as in claim 1, wherein the base plate iscreated from one of a stamping process and a casting process.
 13. Thespindle motor system as in claim 12, wherein the stiffener tab is formedby casting when the base plate is cast.
 14. The spindle motor system asin claim 1, wherein the stiffener tab is shaped to establish apredetermined natural frequency of the base plate axial and bendingmodes of vibration.
 15. The spindle motor system as in claim 1, whereinthe bearing is a fluid dynamic bearing.
 16. In a spindle motor systemincluding a bearing defined between a stationary component and arotatable component, wherein the stationary component and the rotatablecomponent are positioned for relative rotation, wherein the stationarycomponent includes a base plate and a stator, and wherein the statorcomprises at least one stator tooth, a method comprising: stiffening thebase plate by employing a stiffener tab extending from the base plate,wherein: i.) at least a portion of the stiffener tab is dimensioned tofit and positioned circumferentially adjacent to the at least one statortooth of the stator; and ii.) the stiffener tab extends along a radiallyextending span of the base plate.
 17. (canceled)
 18. The method as inclaim 16, wherein the stiffener tab is situated axially below the statorwhile being circumferentially adjacent to the stator.
 19. The method asin claim 16, wherein the stator comprises a first stator tooth and asecond stator tooth, and wherein at least a portion of the stiffener tabis positioned circumferentially adjacent to the first stator tooth andthe second stator tooth.
 20. The method as in claim 16, wherein one of:the stiffener tab is formed from a portion of the base plate that isdisplaced and defines a hole within the base plate; and the stiffenertab is formed from a material that is attached to the base plate. 21.The method as in claim 16, wherein the stiffener tab is connected to aportion of the stator for further stiffening the base plate.
 22. Themethod as in claim 16, wherein the stiffener tab is formed withdimensions for filling an unoccupied area defined adjacent to thestator, wherein the dimensions of the stiffener tab are maximized to anextent without interfering with any motion of the spindle motor system.23. The method as in claim 16, wherein the stiffener tab is shaped toestablish a predetermined natural frequency of the base plate axial andbending modes of vibration.
 24. An apparatus comprising: a statorincluding at least one tooth; and a base plate including at least oneassociated stiffener tab that is configured to be circumferentiallyadjacent to the at least one tooth, wherein: i.) the stator is disposedadjacent to the base plate; and ii.) the stiffener tab extends along aradially extending span of the base plate.